Using the proper leavening is important in creating a picture-perfect cake

Earlier this week, I went to a Baker’s Dozen meeting, and joined about 120 other baking enthusiasts for lunch at the California Culinary Academy and a panel with Harold McGee and Shirley Corriher — both of whom know more about the practical chemistry of cooking than just about anybody else I know.

I don’t think I’ve ever been in a baking discussion when baking powder and baking soda hasn’t been brought into the conversation. Corriher says it’s one of the biggest problems she sees in cookbooks. “In hundreds and hundreds of cookbooks, cakes are over leavened,” she said. The formula is 1 to 1 1/4 teaspoons of baking powder per cup of flour, or 1/4 teaspoon of baking soda per cup of flour.

Another FAQ: the dangers of aluminum in baking. Harold McGee answered: “You get more from eating a pickle than you do from eating half a cake.”

Other tips gleaned:

Ripening persimmons. To keep them crunchy, McGee says they need to be deprived of oxygen. He recommends wrapping them tightly in freezer bags used for vacuum sealing. The fruit will ripen, but will remain crunchy rather than mushy.

Smoking points in oil: “If fresh and refined, oil has a high smoke point,” says McGee. The most important thing isn’t the kind of oil, he says, but its purity.

Preventing moldy berries: McGee found that high temperatures suppress the growth of mold. He says to plung the berries in 120 degree water, let them sit for 30 seconds, remove and let dry.

Keeping navy beans firm: Put in molasses or brown sugar, says Corriher. “You can then cook them for days and they stay firm.”

Knowing your starches: Corriher explained that root starches such as arrowroot and tapioca freeze well, and remain clear whether hot or cold. Grain starches are clear when warm, become cloudy as they cool and don’t freeze well. When thickening things, she recommends waiting until the liquid reaches a boil before adding any more thickeners.

Even though these two seem to have written the book on cooking chemistry, Corriher ends with a sobering quote:

“There’s a humbling experience for every cook right around the corner.”